#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#define Swapbit(n) ((n&0x55555555)<<1) | ((n&0xaaaaaaaa)>>1) 
int main()
{
	int n = 11;
	int ret = Swapbit(n);
	printf("ret=%d\n", ret);
	return 0;
}